January 15, 2014

New Software Brings Planetarium-Style Viewing To Wider Audience

Scientists from the Fraunhofer Institute for Open Communication Systems FOKUS in Berlin have teamed up with graphics card manufacturer NVIDIA to create a new kind of technique for projecting images in a planetarium-like style.

The new technology could help bring the concept of projecting images onto contoured surfaces for a virtual experience to an even wider audience. Dome planetariums use numerous projectors like this to recreate the night sky in a way that makes you feel as if you could reach out and touch the Milky Way. Now, a new technique using “desktop warping” promises to bring this application beyond the planetarium.

Desktop warping allows a Windows desktop display to be projected onto curved screens, similar to a planetarium. In order to obtain an even picture on a curved screen, the projectors must be calibrated with one another. Each of the projectors shows just a part of the image, which together helps to form the whole picture.

“It’s a bit like a puzzle. Every piece has to slot in exactly with the others to get the right picture,” said Manuel Schiewe, a FOKUS researcher who has dedicated a lot of time to the topic.

Projectors need to be calibrated in such a way that the images being projected are of equal brightness and suitable for a curved surface. In order to do this, the team had to recalibrate the images, which were originally intended for a flat screen.

“As soon as the position of the projectors moved even slightly, we had to step in and make manual adjustments,” said Schiewe.

Researchers at Fraunhofer FOKUS’s laboratories in Berlin developed a piece of software that automatically calibrates images to match the projection screen. The team used cameras to capture test images generated by the projects. Software was then used to calculate the current calibration of the images on the projection screen. Once the software has all the information that it needs to put up the proper calibration and brightness of the image, it is able to project like a modern-day planetarium.

“Today, planetariums, theme parks and simulators use the 'Projector auto-alignment’ tool to guarantee an even picture on large contoured surfaces,” says Schiewe.

This technology had previously only been available in combination with Fraunhofer FOKUS’s media player, which is designed for formats like films, images, text or graphics. Projecting any type of content means that researchers need to use special software and hardware.

“That is why we took the decision to integrate the automatic calibration software straight into graphics cards’ drivers. This way, the whole Windows desktop – and any Windows pro- grams – automatically adjust to curved projection screens,” said Schiewe.

“Companies can easily make the most of being able to project onto any surface using their on-board graphics card. Their staff have more ways to communicate with one another, and can do so in a targeted manner. It’s easier, too, to exchange and present content more effectively – even over long distances.”